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1.
Nature ; 572(7767): 86-90, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31332388

RESUMO

Special quantum states are used in metrology to achieve sensitivities below the limits established by classically behaving states1,2. In bosonic interferometers, squeezed states3, number states4,5 and 'Schrödinger cat' states5 have been implemented on various platforms and have demonstrated improved measurement precision over interferometers using coherent states6,7. Another metrologically useful state is an equal superposition of two eigenstates with maximally different energies; this state ideally reaches the full interferometric sensitivity allowed by quantum mechanics8,9. Here we demonstrate the enhanced sensitivity of these quantum states in the case of a harmonic oscillator. We extend an existing experimental technique10 to create number states of order up to n = 100 and to generate superpositions of a harmonic oscillator ground state and a number state of the form [Formula: see text] with n up to 18 in the motion of a single trapped ion. Although experimental imperfections prevent us from reaching the ideal Heisenberg limit, we observe enhanced sensitivity to changes in the frequency of the mechanical oscillator. This sensitivity initially increases linearly with n and reaches a maximum at n = 12, where we observe a metrological enhancement of 6.4(4) decibels (the uncertainty is one standard deviation of the mean) compared to an ideal measurement on a coherent state with the same average occupation number. Such measurements should provide improved characterization of motional decoherence, which is an important source of error in quantum information processing with trapped ions11,12. It should also be possible to use the quantum advantage from number-state superpositions to achieve precision measurements in other harmonic oscillator systems.

2.
Cancer ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804691

RESUMO

BACKGROUND: Sexual dysfunction is a significant complication of treatment for many adult-onset cancers. However, comparatively less is known about sexual dysfunction in adult childhood cancer survivors (CCSs). Research has been limited by the exclusion of specific cancers (e.g., central nervous system [CNS] tumors) and the lack of validated measures, which makes it difficult to understand the nature and prevalence of sexual dysfunction in CCSs. METHODS: A total of 249 adult CCSs (aged 18-65 years) enrolled in Project REACH, a prospective cohort study, and completed measures of physical and mental health, including sexual dysfunction. Participants scoring ≤19 on the Female Sexual Function Index 6 or ≤21 on the International Index of Erectile Function 5 were classified as experiencing sexual dysfunction. Analyses examined the relationships between sexual dysfunction and demographic, disease, treatment, and health variables. RESULTS: A total of 78 participants (32%) experienced clinically significant sexual dysfunction. In univariate analysis, sexual dysfunction was significantly associated with CNS tumor diagnosis (odds ratio [OR], 2.56) and surgery (OR, 1.96) as well as with health variables such as fatigue (OR, 3.00), poor sleep (OR, 2.84), pain (OR, 2.04), depression (OR, 2.64), poor physical health (OR, 2.45), and poor mental health (OR, 2.21). Adjusted analyses found that CNS tumor diagnosis (p = .001) and health variables (p = .025) contribute significantly to sexual dysfunction in CCSs. CONCLUSIONS: Approximately one third of adult CCSs report clinically significant sexual dysfunction, which underscores a significant screening and treatment need. However, because available measures were developed for survivors of adult cancers, research to create a sexual health measure specifically for adult CCSs is necessary to better identify the sexual health concerns of this vulnerable population.

3.
Phys Rev Lett ; 126(25): 250507, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34241508

RESUMO

Characterization and suppression of noise are essential for the control of harmonic oscillators in the quantum regime. We measure the noise spectrum of a quantum harmonic oscillator from low frequency to near the oscillator resonance by sensing its response to amplitude modulated periodic drives with a qubit. Using the motion of a trapped ion, we experimentally demonstrate two different implementations with combined sensitivity to noise from 500 Hz to 600 kHz. We apply our method to measure the intrinsic noise spectrum of an ion trap potential in a previously unaccessed frequency range.

4.
JMIR Res Protoc ; 12: e52315, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38019571

RESUMO

BACKGROUND: Young adult cancer survivors (YACS) are at elevated risk for chronic insomnia, even years after completing treatment. In addition to potential health consequences, insomnia can interrupt social, educational, and vocational development just as they are trying to "make up" for time lost to cancer. Cognitive behavioral therapy for insomnia (CBTI) is recommended as first-line treatment for insomnia but remains largely unavailable to YACS due to several barriers (ie, shortage of trained providers, geographic limitations, financial limitations). Traditional CBTI has not been adapted to meet YACS' unique developmental and circadian challenges. To improve availability of effective behavioral insomnia treatment for this population, we developed the Sleep Treatment Education Program for Young Adult Cancer Survivors (STEP-YA), a low-intensity educational intervention delivered virtually online. OBJECTIVE: In this phase 2 "proof of concept" trial, primary aims are to test the efficacy of STEP-YA to improve insomnia symptoms and mood in YACS and assess the utility of individualized coaching to improve treatment effects. A secondary aim will explore participant variables associated with clinically significant response to STEP-YA. METHODS: This 2-arm randomized prospective trial will enroll 74 off-treatment YACS aged 20 years to 39 years with clinically significant insomnia. Each participant completes the STEP-YA intervention in a 1-on-1 synchronous online session led by a trained interventionist following a structured outline. The 90-minute intervention presents educational information on the development of insomnia after cancer and offers specific suggestions for improving insomnia symptoms. During the session, participants review the suggestions and develop a personalized sleep action plan for implementing them. After the session, participants are randomized to either the coaching condition, in which they receive 2 telephone coaching sessions, or the no-coaching condition, which offers no subsequent coaching. The Insomnia Severity Index (ISI) and the Profile of Mood States: Short Form (POMS-SF) are assessed at baseline and 4 and 8 weeks postintervention. RESULTS: Enrollment began in November 2022, with 28 participants currently enrolled. We anticipate recruitment will be completed in 2024. The primary endpoint is a change in ISI score from baseline to 8 weeks postintervention. The secondary endpoint is change in mood symptoms (POMS-SF) from baseline to 8 weeks postintervention. Change scores will be treated as continuous variables. Primary analyses will use ANOVA methods. A within-subjects analysis will examine if the STEP-YA intervention is associated with significant changes in insomnia and mood over time. A 2-way ANOVA will be used to evaluate the utility of coaching sessions to improve treatment effects. CONCLUSIONS: Chronic insomnia has significant negative effects on YACS' medical, educational, and psychological functioning. STEP-YA aims to address their needs; study results will determine if the intervention warrants future effectiveness and dissemination studies and if individualized coaching is necessary for adequate treatment response. TRIAL REGISTRATION: ClinicalTrials.gov NCT05358951: https://clinicaltrials.gov/study/NCT05358951. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/52315.

5.
Am J Occup Ther ; 65(1): 86-94, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21309375

RESUMO

We identified factors associated with occupational therapists' involvement as children receiving early intervention services transition into preschool. A survey was sent to members of the American Occupational Therapy Association's School System Special Interest Section. The highest ranked factor for respondents in early intervention was understanding their role (mean [M]= 4.96, standard deviation [SD] = 1.26, n = 78) and for respondents in preschool programs it was having preschool staff value their participation (M = 4.84, SD = 1.46, n = 248). Preschool occupational therapists' relationship with early intervention providers, employer-based supports, and knowledge of the transition process were significantly associated with their involvement in two transition planning areas: collaboration with early intervention programs (p < .001) and family support (p < .001). Findings suggest that practices that enhance relationships among programs influence occupational therapist involvement. Implications for formal training to support involvement in the transition process are discussed.


Assuntos
Crianças com Deficiência/reabilitação , Intervenção Educacional Precoce/organização & administração , Acontecimentos que Mudam a Vida , Terapia Ocupacional/organização & administração , Instituições Acadêmicas , Adulto , Pré-Escolar , Humanos
6.
Phys Rev X ; 10(3)2020.
Artigo em Inglês | MEDLINE | ID: mdl-34408918

RESUMO

We report on the observation of magnetic Feshbach resonances in a Fermi-Fermi mixture of ultracold atoms with extreme mass imbalance and on their unique p-wave dominated three-body recombination processes. Our system consists of open-shell alkali-metal 6Li and closed-shell 173Yb atoms, both spin polarized and held at various temperatures between 1 and 20 µK. We confirm that Feshbach resonances in this system are solely the result of a weak separation-dependent hyperfine coupling between the electronic spin of 6Li and the nuclear spin of 173Yb. Our analysis also shows that three-body recombination rates are controlled by the identical fermion nature of the mixture, even in the presence of s-wave collisions between the two species and with recombination rate coefficients outside the Wigner threshold regime at our lowest temperature. Specifically, a comparison of experimental and theoretical line shapes of the recombination process indicates that the characteristic asymmetric line shape as a function of applied magnetic field and a maximum recombination rate coefficient that is independent of temperature can only be explained by triatomic collisions with nonzero, p-wave total orbital angular momentum. The resonances can be used to form ultracold doublet ground-state molecules and to simulate quantum superfluidity in mass-imbalanced mixtures.

7.
Appl Environ Microbiol ; 74(5): 1667-70, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18203862

RESUMO

We investigated the bacterial communities of nine Bartonella-positive fleas (n = 6 Oropsylla hirsuta fleas and n = 3 Oropsylla montana fleas), using universal primers, clone libraries, and DNA sequencing. DNA sequences were used to classify bacteria detected in a phylogenetic context, to explore community assembly patterns within individual fleas, and to survey diversity patterns in dominant lineages.


Assuntos
Bartonella/genética , Ecossistema , Variação Genética , Filogenia , Sciuridae/parasitologia , Sifonápteros/microbiologia , Animais , Sequência de Bases , Colorado , Primers do DNA/genética , Evolução Molecular , Biblioteca Gênica , Funções Verossimilhança , Modelos Genéticos , Dados de Sequência Molecular , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Especificidade da Espécie
8.
Aust J Physiother ; 53(1): 41-5, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17326737

RESUMO

QUESTION: Does faulty proprioceptive input disrupt the internal model of the body that the brain uses to control movement? DESIGN: Randomised, within-participant experimental study. PARTICIPANTS: Twenty-two (13 F) healthy adults. INTERVENTION: Participants performed a motor imagery task that involved making left/right judgements of pictured right and left hands in 16 different postures under five conditions involving stimuli being applied to the experimental (L) hand. The five conditions were: vibration (of the wrist extensor tendons to elicit the illusion of wrist flexion), sham (vibration of the ulna styloid), active flexion, passive flexion, and control (no stimulus). OUTCOME MEASURES: Accuracy and response time of the control (R) hand in making left/right judgements of the pictures. RESULTS: Response time during vibration was longer for those who reported the illusion of wrist flexion (n = 18) than for those who did not (p < 0.01) whereas accuracy was unaffected (p = 0.71). In those who reported the illusion, accuracy was unaffected by condition, hand or picture (p > 0.21). Response time during vibration was 910 ms longer (95% CI 730 to 1090) for pictures of the experimental (L) hand (mean 2731 ms, 95% CI 2543 to 2918) than it was for pictures of the control (R) hand (mean 1822 ms, 95% CI 1634 to 2009), and approximately 580 ms longer (95% CI 380 to 785) for pictures of either hand during any other condition (p < 0.025). CONCLUSION: Faulty proprioceptive input disrupted this motor imagery task, which suggests it can disrupt the model of the limb that the brain uses for movement.


Assuntos
Ilusões/fisiologia , Propriocepção/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Movimento/fisiologia , Tempo de Reação/fisiologia , Análise e Desempenho de Tarefas , Vibração , Punho/fisiologia
9.
Anim Nutr ; 3(1): 77-84, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29767127

RESUMO

Three experiments were conducted to evaluate the phosphorus (P) utilization responses of pigs and broiler chickens to dietary supplementation with antimicrobials and phytase and to determine if P digestibility response to phytase is affected by supplementation with antimicrobials. Experiment 1 used 4 diets (a basal negative control formulated to contain 0.41% total P and 0.71% calcium [Ca] without added antimicrobials, basal negative control with added carbadox, basal negative control with added tylosin, or basal negative control with added virginiamycin) and six 18-kg barrows in individual metabolism crates per diet. There was no effect of antimicrobials on P and Ca digestibility or retention. Carbadox supplementation increased (P < 0.05) digestibility and retention of gross energy (GE) and supplementation with tylosin increased (P < 0.05) N retention relative to the basal negative control diet. Experiment 2 used eight 19-kg barrows in individual metabolism crates per treatment and 9 dietary treatments arranged in a 3 × 3 factorial of antimicrobials (none, tylosin, or virginiamycin) and phytase (0, 500, or 1,500 FTU/kg). Phytase addition to the diets linearly increased (P < 0.05) apparent total tract digestibility or retention of P, Ca, nitrogen (N) and GE. Supplementation with antimicrobials did not affect apparent total tract digestibility or retention of P, Ca, N or GE. There were linear effects (P < 0.01) of phytase on Ca utilization in diets that were not supplemented with antimicrobials but only tendencies (P < 0.10) in diets supplemented with tylosin or virginiamycin. Phytase linearly improved (P < 0.05) N utilization in diets supplemented with tylosin or virginiamycin but not in diets without added antimicrobials. Experiment 3 was a broiler chicken experiment with the same experimental design as Exp. 2 but feeding 8 birds per cage and 10 replicate cages per diet. Antimicrobial supplementation improved (P < 0.05) feed efficiency and adding tylosin improved (P < 0.05) tibia ash but did not affect nutrient utilization. Dietary phytase improved (P < 0.01) growth performance, tibia ash and apparent ileal digestibility and retention of P regardless of antimicrobial supplementation. Overall, phytase supplementation improved growth performance and nutrient digestibility and retention, regardless of supplementation of diets with antimicrobials. Supplementation of diets with antimicrobials did not affect P digestibility or retention because of a lack of interaction between antimicrobials and phytase, there was no evidence that P digestibility response to phytase is affected by supplementation with antimicrobials.

10.
Eur J Pain ; 10(3): 219-24, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16490729

RESUMO

BACKGROUND: People in pain, or expecting pain, sometimes bias their attention towards pain-relevant cues. Perhaps they also bias their attention towards the body part in question. AIM: To determine if experimentally induced pain, and the expectation of pain, involve an information processing bias towards the hand in question. METHODS: Seventeen asymptomatic subjects performed a hand laterality recognition task during three conditions: control, during hand pain induced by intramuscular injection of hypertonic saline (pain), and during expectation of hand pain, induced by isotonic saline injection (expectation). Mean response time (RT) was determined for three 45 s epochs within each condition and RT was compared between hands, conditions and epochs using a 2 x 3 x 3 repeated measures multivariate analysis of variance. RESULTS: There was a hand x condition interaction and a hand x condition x epoch interaction (p<0.05 for both). RT to recognise the opposite hand was approximately 600 ms longer during epochs when subjects were in pain or expected pain than during control trials. During those epochs, RT to recognise the opposite hand was approximately 600 ms longer than RT to recognise the injected hand, which was consistent across conditions and across epochs. CONCLUSIONS: Both pain and the expectation of pain increased RT to recognise the opposite hand. The findings are consistent with a bias in information processing toward the painful or impending painful hand.


Assuntos
Atenção , Lateralidade Funcional , Dor/psicologia , Percepção , Reconhecimento Psicológico , Adulto , Viés , Feminino , Mãos , Humanos , Masculino , Dor/induzido quimicamente , Tempo de Reação , Solução Salina Hipertônica , Enquadramento Psicológico
11.
Nat Commun ; 1: 53, 2010 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-20975720

RESUMO

Soil microorganisms dominate terrestrial biogeochemical cycles; however, we know very little about their spatial distribution and how changes in the distributions of specific groups of microbes translate into landscape and global patterns of biogeochemical processes. In this paper, we use a nested sampling scheme at scales ranging from 2 to 2,000 m to show that bacteria have significant spatial autocorrelation in community composition up to a distance of 240 m, and that this pattern is driven by changes in the relative abundance of specific bacterial clades across the landscape. Analysis of clade habitat distribution models and spatial co-correlation maps identified soil pH, plant abundance and snow depth as major variables structuring bacterial communities across this landscape, and revealed an unexpected and important oligotrophic niche for the Rhodospirillales in soil. Furthermore, our global analysis of high-elevation soils from the Andes, Rockies, Himalayas and Alaskan range shows that habitat distribution models for bacteria have a strong predictive power across the entire globe.


Assuntos
Bactérias/genética , Microbiologia do Solo , Bactérias/classificação , Biodiversidade , Geografia , Dados de Sequência Molecular
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